A communication system permits the communication of information between two or more communication stations. The communication stations are connected by a communication channel upon which a communication signal is transmitted. The communication signal includes the information which is to be communicated between the communication stations. In a two-way communication system, a communication station includes both a transmitter portion and a receiver portion operable to transmit and to receive, respectively, communication signals.
A radio communication system is a communication system in which the communication channel formed between the communication stations is a radio channel defined upon a portion of the electromagnetic spectrum. When a communication station operable in such a communication system includes both a transmitter portion and a receiver portion, the communication station forms a radio transceiver, capable of two-way, radio communication with another communication station. Because communication signals can be transmitted between radio transceivers on radio channels, wire line connections are not required to effectuate communications in a radio communication system. Thereby, communications are possible by way of a radio communication system when formation of a wire line connection between the communication stations would be impractical.
A cellular communication system is an exemplary radio communication system. Cellular communication systems, constructed according to various standards, have been installed throughout significant portions of the world. A subscriber to a cellular communication system is able to communicate telephonically by way of a radio transceiver, typically referred to as a mobile station, when the mobile station is positioned within an area encompassed by the communication system. Telephonic communication of both voice information and data information is permitted in such networks.
Advancements in digital communication techniques have facilitated the implementation of new cellular, and other, communication systems capable of communicating increased amounts, and types, of data. For instance, a proposed cellular communication system set forth in the specification of a CDMA2000 standard provides for the performance of multi-media communication services. Multi-media communications pertain, generally, to the communication of two, or more, separate types of information, such as voice and data information.
QoS (quality of service) level parameters are defined in the specification of the proposed CDMA2000 standard. QoS level parameters are analogously also defined in standards pertaining to other cellular communication systems. QoS level parameters define standards by which to measure, or ensure, minimum communication quality levels. A QoS level parameter can be used in service initiation and service modification. A QoS level parameter can be used during service negotiations in the initiation of performance of a communication service as well as to modify service levels during performance of a communication service. A QoS level parameter defines a communication service in terms, e.g., bit-error rates, service delays, as well as other types of performance measures. Performance of a communication service at a level at least corresponding to a selected performance measure by which a QoS level parameter is defined ensures that the communication service is performed at a communication quality level associated therewith. The QoS level parameter, therefore, is a quantifiable parameter associated with a communication quality level.
Different communication services might necessitate different levels of communication qualities to ensure their performance. And, different subscribers to a communication system might be willing to subscribe to different levels of service. For instance, one subscriber might require that a communication service be performed at a greater data transmission rate than another subscriber. A subscription for service at a QoS level ensuring performance of the communication service at the greater transmission rate can be selected to meet the requirements of the subscriber.
The amount of gain applied to a communication signal at a transmitter portion of a communication station is, in part, determinative of a performance measure associated with a QoS level parameter. To ensure that a communication service is performed at a selected QoS level, the gain by which the communication signal transmitted to perform such communication service must be selected to be at least great enough to perform the communication service at the desired QoS level. However, the level of gain at which a communication signal is transmitted in a CDMA (code-division multiple-access) communication system cannot merely be increased without constraint. A communication signal of an inordinately high level of gain interferes with concurrently-generated communication signals by other communication stations operable in the CDMA communication system. Permitted levels of gain by which a communication station can amplify a communication signal must therefore be controlled. In the proposed CDMA2000 communication system, the gain is selected pursuant to service negotiation. That is to say, control apparatus of the proposed CDMA2000 system controls whether a request to perform a communication service at a desired QoS level shall be permitted.
While channel gains associated with dedicated data channels are defined in CDMA2000 standard proposals, a manner by which to use feedback power control to adjust the levels of gain has not been set forth. A manner by which to effectuate power control by which to control the levels of gain by which communication signals are amplified would advantageously improve system efficiency.
It is in light of this background information related to communications in a radio communication system that the significant improvements of the present invention have evolved.